The combination of the Kestrel Wind Turbine and Grundfos SQFlex range gives efficient water delivery from a wind speed of 3m/s. The maximum pump output is achieved from wind speeds of 5m/s and above. The Maximum Power Point Tracking (MPPT) function of the pump was enhanced by the efficient performance of the Kestrel. The pump optimises the available energy and only causes momentary stalling of the wind turbine at very low wind speeds. No additional controller is required and since the Kestrel outputs dc electricity, no rectifier system is necessary.

See systems in action:

• Pietersburg, South Africa

In a low wind region near the Mozambiquan border, an e300 (1kW) with a patented Kestrel Voltage Limiter (only required in a 110Vdc system) was installed with the Grundfos Controller and SQFlex pump. The Kestrel Voltage Limiter was installed to optimise the potential output. The installation has been operational for 2 years without any failure. Installed by Giel de Kok.

• Water for All, South Africa

Direct system, an e300 (1kW) with Grundfos Controller and SQFlex pump (direct system is 80Vdc) was installed in a school to pump water as part of a water development project. System has been running well since 2007, with no issues. Installed by Carl Nienaber.